Are you referring to the patterns-backup#.ini files in the adblockplus folder, in the Profile folder??

If so, you can decrease the number of backup files that ABP saves.
extensions.adblockplus.patternsbackups - default is 5
Right-click that pref and select Modify

http://kb.mozillazine.org/About:config

Yes, patterns-####.ini. I reset the default from 5 to 2, but it didn't seem to make a difference. I stopped Mozbackup after it went through more than 3,000 INI files.

What if I set the number to 1? to 0?

And I see the next item is patternsbackupinterval, whose default is 24. What is this, and should this number also be changed?

Thanks.

patterns-####.ini may be the real problem! I figure that you should only have one file like that, with a maximum of 5 named patterns-backup1.ini thru patterns-backup5.ini. I suspect there is something wrong with your Firefox installation - and / or some type of security program screwing with something in Firefox causing that many files to be created.

Please verify my suspicion that the /adblockplus/ folder is loaded with patterns-####.ini files. See my screenshot below to see what mine /adblockplus/ data folder look like.

One more thing, it might not be a bad idea to post about that issue in the AdblockPlus forum, to see if they have run into this before.
http://adblockplus.org/forum/
Even If they haven't run into this before, someone there might have an idea as to what might cause that to happen. I haven't heard of this before.

Whoops, as far as your original question about preventing Mozbackup from saving AdblockPlus files.....

I haven't ever found the need for using Mozbackup, so I don't have any experience with that program. But from reading thru the Mozbackup manual, there seems to be no fine-grained control for what is or isn't backed-up, all I can see is the category Extensions. I don't know if that is only the /extensions/ folder in the Profile folder (which I suspect is what that category controls pertains to), or if it includes any separate files or folders placed in the Profile folder when an extension is installed or starts saving data. I seriously doubt if Mozbackup is "smart enough" to recognize that /adblockplus/ folder as being part of an extension, and to back that folder up, too.

Thank you, edmeister, for your replies. I set Mozbackup not to back up any adblockplus files, and the backup took exactly 1 second and was 2,300 Kb!

You had mentioned not using Mozbackup--what do you do to back up Firefox--anything at all? I suppose I could just reinstall it and then reinstall all the plugins and extensions, both as a "backup" plan and if, as you suggested, my Firefox install is corrupted.

Thanks again for sticking with me on this.

I save a copy of the Profile folder to a USB drive.

How many of those patterns.ini files are there?

Sorry to take so long with this response. It appears there are over 3,000 patterns.ini files. This I should uninstall Firefox and reinstall with new add-on downloads?

And I see my default Firefox profile is more than 2.7Gb. Is that normal?

I doubt if Firefox is causing multiple patterns.ini files, or AdblockPlus. I would suspect something like an anti-virus application as preventing data from being saved to the original patterns.ini file, thus spawning multiples of that file.

What are the dates & times of those multiple files? Any type of related timing (pattern) as to when each of those files was created?

There are 4,281 patterns in the Adblockplus folder. It appears that 20-40 are being created every day--like, every time I use Firefox. What if I removed Adblockplus completely and then reinstalled it?

I use Microsoft Security Essentials.

I haven't heard of any problems like that caused by MSE.

My advice is to post this issue (with so many patterns.ini files being created and saved) in the Adblock Plus support forum.
http://adblockplus.org/forum/

Will do. Thanks.